Dr Woo Suk Hwang, once regarded as the world's leading stem cell pioneer, was branded a national disgrace yesterday in his home country of South Korea, after an investigation found that the research on which his reputation rested was fabricated.

Officials at Seoul National University, where Dr Hwang carried out the studies, began an investigation into his work last month after co-workers accused him of inventing results in a series of high-profile scientific papers that claimed to make leaps forward in stem cell research. The papers were published in the US journal Science in the past two years.

Reporting the results of its investigation yesterday, the university committee said data in Dr Hwang's key papers on human cloning were fabricated.

"The scientific bases for claiming any success are wholly lacking," the report said. "That the publications are fabricated alone mandates severe penalty by the academia. These individuals cannot be regarded to represent science in Korea."

Dr Hwang, who resigned last month, also faces the prospect of prosecution after officials said they may launch an investigation after reviewing the contents of the university's report, according to Hwang Hee-chul, the No 2 official at the supreme public prosecutors' office in Seoul.

Dr Hwang began his career as a veterinarian at Seoul National University and rose within the scientific community when he published a series of groundbreaking papers on cloning.

In 2004, he claimed to be first in the world to clone a human embryo and harvest stem cells from it.

Last year he published another important study that reported the creation of 11 batches of stem cells, each tailored to patients with different diseases. The research gave hope to countless patients with terminal illnesses ranging from Parkinson's disease to Alzheimer's.

The apparent success propelled Dr Hwang to almost God-like status. He was dubbed "the pride of Korea". Korean Air offered him first class tickets for life. The government put his face on a stamp and gave him millions of dollars of funding to pursue the research.

But only one key research paper, which announced the cloning of Snuppy the Afghan hound in Nature last August, was found to be true.

With the breathtaking progress Dr Hwang claimed to have made now discredited, scientists have been forced back to the drawing board.

"This has set us back several years. It was as if Dr Hwang had sent us a picture of him on top of Everest, but it happened not to be Everest. He lied to us about that and Everest is still there to climb. It's a challenge and it's a biggy," said Chris Shaw, a neurologist at King's College London who with Edinburgh University's Ian Wilmut, creator of Dolly the sheep, heads one of only two groups in Britain to hold a human cloning licence.

"I feel bitterly disappointed and very let down. This fraud has hurt the confidence and hope of a lot of patients, and I see that in the clinic. If you've got a fatal illness and you hear there's a therapy on the horizon, you find out about it," he added.

While cloning represents only a small proportion of all stem-cell research, many scientists believed it held great promise.

Stem cells taken from cloned embryos could potentially lead to new treatments tailored to an individual patient's condition, raising the prospect of being able to regenerate damaged tissues and organs without being rejected by the immune system.

Disappointment among scientists was more acute because of the substantial backing and support Dr Hwang enjoyed.

"The problem is that Dr Hwang had a better chance to crack this than anyone else, because of his extraordinary access to fresh human eggs in their thousands, which is going to be very difficult to reproduce anywhere else in the world, and his support from the government that [meant] he had so much money made available to him," said Professor Shaw

Miodrag Stojkovic, who cloned the first human embryo in Europe last year at Newcastle University, but left in December to work at the £274m Prince Felipé research centre in Valencia, said Dr Hwang's actions were a mystery but that pressure on researchers to get results was intense.

Dr Hwang used more than 2,000 fresh eggs from 129 women donors, an amount most researchers would not get to experiment with in a lifetime. Some of the eggs were later discovered to be donated by Dr Hwang's own lab staff, provoking ethical objections from other researchers.

The investigation reveals that there is still hope for scientists involved in cloning research. Official tests in Dr Hwang's laboratory showed that his group succeeded in generating cloned human blastocysts, tiny balls of cells that have the potential to grow into embryos.

"That, and Snuppy, are at least two bits of good news," said Professor Stojkovic. "But this is definitely a step back . We all relied not just on Hwang's results, but his advice on materials to use, what kind of eggs work best and the like.

"When you take these papers out, you are left wondering what information was correct and what wasn't. The lesson is that when you're doing some work, rely on yourself and learn from your own experience." Professor Shaw said that the scientific journals must also improve the checks they have in place for detecting fraud. "When there's a fundamental leap forward, the evidence has to be extremely well scrutinised. They ought to consider getting independent laboratories to verify findings, as was done with Dolly the Sheep," he said.

Footnote

Cloning

The process of creating a genetic copy of a cell or organism. To clone an embryo, scientists pluck the nucleus from a donated cell, often from skin, and squirt it into an egg that has had its own nucleus removed. Stimulating the cell makes it divide, eventually into an embryo.

Stem cell therapies

Some researchers believe that since embryonic stem cells can form any tissue in the body, they could be used to grow organs and tissues to replace those ravaged by disease and trauma. More likely is that research on stem cells will lead to drugs that induce stem cells inside damaged organs to repair themselves.

Scientific papers

Dr Woo Suk Hwang's team published two papers claiming huge advances in human cloning research. The first, published in the US journal Science in February 2004, reported the cloning of 30 human embryos. The second, published in Science in May 2005, reported that the researchers had created stem cells genetically tuned to 11 patients with different diseases. A third paper, announcing the cloning of Snuppy (for Seoul National University puppy) was published in Nature in August 2005 and was not found to be fabricated.

Investigation

Seoul National University opened its investigation into Dr Woo Suk Hwang's work on December 11 2005 after co-workers raised ethical concerns about eggs donated by female researchers, and claimed data in key papers was fabricated.